Field
The present disclosure generally relates to field-effect transistor (FET) structures and radio-frequency (RF) devices such as switches having such FET structures.
Description of the Related Art
A field-effect transistor (FET) can be utilized as a switch for radio-frequency (RF) applications. FET-based switches, such as silicon-on-insulator (SOI) switches are used in, for example, antenna switch modules and front-end modules. Such applications typically benefit from a SOI transistor feature of ideal or nearly ideal isolation.
Typically, an SOI device is rated for only a few volts. Accordingly, several SOI switches having relatively large width/length ratio can be arranged in series to provide RF switching functionality. Such a configuration voltage-divides the RF signal being switched, thereby mitigating breakdown concerns and improving reliability in conditions involving, for example, high RF power/voltage or high voltage standing wave ratio (VSWR).